This invention relates to a new spectral sensitized silver halide film. Specifically, the invention relates to a new sensitized silver halide film used to form images by exposure to electronic filmwriter devices and a method for forming the image.
It is well known to expose silver halide photographic elements using light radiation, the silver halide element being usually placed in a camera. Electronic filmwriter devices represent a different means of exposing a photographic film other than a camera. These devices usually contain three different light sources, one that exposes the red portion of an image, one that exposes the green portion, and one that exposes the blue portion. Examples of electronic filmwriter devices are the Saphire and Solitaire by MGI, Lightjet by CSI, Miruswriter Turbopro II by Mirus Industries, and LVT by Dice. These devices have different types of light sources having different spectral power distributions. The Saphire, Solitaire, and Miruswriter all have CRT light sources, Lightjet contains laser sources, and the LVT contains LED sources.
Information is supplied to the device that digitally describes the original scene""s content. This information originates from either a camera image or a computer. In the case where the camera image is the source of the information to the device, the image is scanned so that digital values can be supplied to the device. The supplied information is then used to expose an output film. In the case where the original image is generated by a computer, the information is already in digital form.
Signal processing of the supplied information is performed within the device to determine the intensity and time of exposures that the three light sources are to give the output film. Typically, when the film is exposed, the filmwriter device must scan over the entire area of the film to expose each color record of the output film. The extent of exposure of the output film, and hence, the amount of dye formation, depends in part on the spectral sensitivity distributions of the film and the spectral power distributions of the light sources of the electronic filmwriter device.
U.S. Pat. No. 4,954,429 discloses a film for laser recording. The disclosed film is spectral sensitized to minimize unwanted dye formation to prevent xe2x80x98color mixing.xe2x80x99 The result is obtained from the specific ratio of the sensitivity of the light sensitive emulsion layers constituting the film.
Often films which are exposed by electronic filmwriter devices are films which are spectrally optimized to be exposed by natural light radiation, not the light source of an electronic filmwriter device. As a result, when these films are used as the imaging media from an electronic filmwriter device, extra xe2x80x98scansxe2x80x99 by the light sources are often needed. It is know that extra scans are often required for proper exposure by the green light source of the filmwriter device. When conventional reversal films are exposed by an electronic filmwriter device, extra scans by the red light source are also often required to decrease the amount of cyan density that forms in the low density region of images. These extra scans undesirably increase the completion time of the image. This affects the throughput of the machine.
This invention provides a photographic element comprising a support having thereon light sensitive silver halide layers comprising at least one red light sensitive silver halide layer, at least one green light sensitive silver halide layer, and at least one blue sensitive silver halide layer, wherein
the green light sensitive silver halide layer has an absorption spectra having a maximum absorption at a wavelength xcexmax from 530 to 560 nm and a half bandwidth less than 50 nm; and
the red light sensitive silver halide layer has an adsorption spectra having a maximum absorption at a wavelength xcexmax from 610 to 640 nm, and exhibiting from 30 nm hypsochromic of the wavelength of maximum absorption and below an area less than 30% based on the total area of the red light sensitive silver halide layer adsorption spectra. This invention also provides a process for forming a photographic image which comprises exposing the above photographic element with light sources from an electronic filmwriter device.
The present invention provides a silver halide element that shows sensitometric advantages when exposed by an electronic filmwriter device. The film of the present invention exhibits increased green and red spectral sensitivities. The increased red and green sensitivities decrease the time the element needs to be exposed by the red and green light sources of the electronic film writer. This provides an advantageous time saving for the completion of the image. Other and further advantages of the invention will appear from the description of the present invention